218138441638 has 8 divisors (see below), whose sum is σ = 352377482688. Its totient is φ = 100679280744.

The previous prime is 218138441627. The next prime is 218138441639. The reversal of 218138441638 is 836144831812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 218138441591 and 218138441600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218138441639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4194970006 + ... + 4194970057.

It is an arithmetic number, because the mean of its divisors is an integer number (44047185336).

Almost surely, 2^218138441638 is an apocalyptic number.

218138441638 is a deficient number, since it is larger than the sum of its proper divisors (134239041050).

218138441638 is a wasteful number, since it uses less digits than its factorization.

218138441638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8389940078.

The product of its digits is 884736, while the sum is 49.

The spelling of 218138441638 in words is "two hundred eighteen billion, one hundred thirty-eight million, four hundred forty-one thousand, six hundred thirty-eight".